📚 Topic Summary
Biogeochemical cycles are the pathways through which essential elements like carbon, nitrogen, phosphorus, and water move between living organisms and the nonliving environment. These cycles involve biological, geological, and chemical processes, ensuring the continuous availability of these elements for life. Understanding these cycles is crucial for comprehending how ecosystems function and how human activities can impact them.
These cycles are essential for maintaining life on Earth. They describe the movement of elements or molecules through both biotic (living) and abiotic (non-living) components of an ecosystem, ensuring their availability for organisms. Human activities can significantly disrupt these cycles, leading to environmental consequences like pollution and climate change.
🧪 Part A: Vocabulary
Match each term with its correct definition:
- Term: Carbon Cycle
- Term: Nitrogen Fixation
- Term: Phosphorus Cycle
- Term: Water Cycle (Hydrologic Cycle)
- Term: Denitrification
- Definition: The process by which bacteria convert nitrates into nitrogen gas, releasing it back into the atmosphere.
- Definition: The continuous movement of water on, above, and below the surface of the Earth.
- Definition: The biogeochemical cycle that describes the movement of carbon through the atmosphere, oceans, land, and living organisms.
- Definition: The conversion of atmospheric nitrogen into ammonia, which can be used by plants.
- Definition: The biogeochemical cycle that describes the movement of phosphorus through rocks, water, soil, and organisms.
📝 Part B: Fill in the Blanks
Complete the following paragraph using the words provided: evaporation, respiration, photosynthesis, decomposition, precipitation.
The water cycle involves several key processes. __________ is the process where water changes from a liquid to a gas and enters the atmosphere. Water returns to the Earth's surface through __________. Living organisms play a role too; plants use __________ to create energy, and both plants and animals release water back into the environment through __________. Finally, __________ breaks down organic matter, releasing nutrients back into the ecosystem.
🤔 Part C: Critical Thinking
Describe how human activities can disrupt the nitrogen cycle, and explain the potential consequences of these disruptions on ecosystems and human health.